No. 40: Jul-Aug 1985
In a "garage" off the road tunnel running deep under Mont Blanc sits a huge particle detector called Nusex. A second, complementary experiment resides 600 meters below the surface in a Minnesota mine. Both experiments are tuned to measure charged particles of very high energy, especially muons, which penetrate their high rocky ceilings with ease. These two arrays of buried detectors have both picked up fluxes of muons coming from the direction of Cygnus X-3
Now Cygnus X-3 is already classed as a remarkable object because it spews out pulses of X-rays and gamma-rays. It turns out that the muon fluxes arrive in phase with the pulses of gamma-rays and X-rays, and are thus definitely linked to Cygnus X-3. The problem here is that muons are electrically charged particles that would assuredly be thrown far off course by intergalactic magnetic fields if they originated at Cygnus X-3.
The muons, therefore, must be created by electrically neutral particles arriving at the earth's atmosphere from Cygnus X-3. Neutrons can be ruled out because they would decay in transit. X-ray photons and neutrinos have also been ruled out. The only alternative left seems to be some unknown neutral particle generated at Cygnus X-3. Cygnus X-3may be a huge particle accelerator which "may operate in a realm of physics inaccessible on Earth, and the high-energy muons may be the first messengers of that new physics."
(Sutton, Christine; "Subatomic Particles from Space, "New Scientist, p. 18, May 23, 1985.)